This invention relates to a method of manufacturing a polishing element, and particularly to a method of manufacturing an essentially all-metallic polishing element useful for finishing surfaces of both metal and nonmetal objects.
Polishing tools such as files or sandpapers have traditionally been used to polish the surfaces of nonmetal objects (like wood, bamboo, or synthetic resin, for example,) or to polish the surfaces of metal objects (such as aluminum, brass, copper, steel, or the like).
Files are polishing tools made from metallic stocks which, when finished, have teeth formed on one or more surfaces thereof. The teeth have customarily been formed on the files by punching the surfaces of the metallic stock with a chisel. Unfortunately, this method is not easily adaptable to efficient mass-productive techniques. Furthermore, neither the tops of the teeth nor the finished sides of the teeth on the files formed by this method are flat and smooth. In this regard, files having teeth whose tops and sides are not flat and smooth are susceptible to a clogging phenomena which occurs in the recessed parts of the file. Clogging becomes even more apparent when a file is used on nonmetal objects. In addition, due to the extreme difficulty in narrowing the gaps between teeth, files have not generally been considered suitable tools for the final steps required for fine finishing or polishing.
Sandpapers are made by sticking abrasive particles onto a paper or a cloth. Sandpapers can be used for final finishing touches since their faces have very fine meshes. However, during the polishing operation abrasive particles adhered to sandpapers tend to break loose. Not only does the detachment of the abrasive particles shorten the life of the sandpaper, but the particles which come off are a potential cause of further problems. While the pliability of sandpaper permits it to be used with a holder, particle detachment occurs even when a holder is employed.
Whenever a file or sandpaper is utilized, fine scratches can be left on a surface being polished. The arrangement of teeth (in the case of a file) or the arrangement of abrasive particles (which essentially function as teeth in the case of sandpaper) cannot be strictly regulated and hence contribute to the fine scratches left on the finished polished surface.
A file foil is publicly disclosed in Japanese Pat. No. 51-9958 for overcoming problems such as those described above which attend existing polishing tools. The file foil is made of metal but is unlike ordinary files which have metal recesses at points where the file teeth intersect. That is, on the file foils of Japanese Pat. No. 51-9958 the teeth run without a break on the file surface. In addition, the arrangement of the teeth on the file foils is strictly regulated. Yet the file foils are thin and generally lack rigidity. Consequently, the file foils are prone to be damaged.
Some emobdiments of the file foils disclosed in Japanese Pat. No. 51-9958 are adapted to mate with a holder for use. However, when the teeth on the file foils are worn-out, the entire unit including both the file foil and the holder are thrown away. Disposal of the entire unit is neither economical nor advantageous in a waste conscious society. File foils adhered to a holder for use as a polishing tool are not always as durable as desired or are unsuitable for long periods of use. In this respect, the non-rigid file foils tend to detach from a holder under certain conditions of adhesion or very stressful polishing work.
The embodiments of the file foils disclosed in Japanese Pat. No. 51-9958 have a cutting action angle (an angle between a top face of a tooth and a side of the tooth) which becomes wider than 90.degree. (i.e., becomes an obtuse angle). A cutting action angle wider than 90.degree. results in a less than optimum polishing performance. In fact, in cross section the teeth of the file foils disclosed in Japanese Pat. No. 51-9958 are essentially semi-circular. The semi-circular shape of the file teeth result from the electrolytic and reducing methods used in making both the file foil and a metallic mold therefore. In this respect, Japanese Pat. No. 51-9958 is incorporated herein by reference, particularly the steps included in the method of manufacturing such file foils. With respect to the steps of this method, the file foil teeth must be formed in essentially semi-circular shape in order to remove the file foil from its associated metallic mold. Otherwise, considerable difficulty would arise when removing the file foil from the mold. Thus, file foils produced in accordance with the method of Japanese Pat. No. 51-9958 have cutting action angles greater than 90.degree. and teeth which tend to lack the desired rigidity.
In view of the foregoing deficiencies of existing polishing elements, it is an object of this invention to provide a method of manufacturing an essentially all-metallic polishing element having superb rigidity and durability.
An advantage of the present invention is the provision of a method of manufacturing a polishing element which is easily and economically mass-produced.
A further advantage of the present invention is the provision of a method of manufacturing a polishing element whose utilization results in smooth, long-lasting finished surfaces yet which requires less expenditure of effort.